1. Field of the Invention
This invention relates to a keylock switch for transmitting key data for actuating a locking or releasing operation to a lock device through electric contact, and also to a keylock switch system using this keylock switch.
2. Description of the Related Art
Locks of houses and offices, locks of car doors, locks of engine starters, and so forth, generally employ a configuration in which a metal key that appropriately fits to a cylinder of a lock actuates locking and releasing operations.
Electronic locks using input of a personal identification number as a key or using storage media such as a magnetic card, an IC card, a bar code label, etc, as the key have also been put into practical application.
On the other hand, an identification function in automated teller machines installed in financial institutions and a security function of personal computers generally release the lock that is software-wise locked up for a designated processing by inputting a password. These functions, too, can be regarded as an electronic keylock.
These electronic keylock each generally comprise an inputting part for inputting key data as an electronic key, a checking part for checking legality of inputted key data and an operating part for executing a locking/releasing operation in accordance with the checking result.
The inputting part of the electronic keylock is so constituted as to correspond to the kind of a keylock switch which input key data. An electronic keylock system using the input of a personal identification number as a key, for example, is equipped with a numeric keypad as the inputting part for inputting the personal identification number. A system using an storage media as a key includes an IC card reader, a magnetic card reader or a bar code scanner as the inputting part of respective systems in accordance with the kind of the storage media as the key.
The electronic keys such as the input of the personal identification number, the IC card, the bar code, etc, have the feature that forging of such keys is more difficult than that of the conventional metal keys. Conventional metal keys have limited width and number of grooves, the shape and number of teeth, and their combination, that could be formed onto it, so the variation of metal keys is therefore limited. In contrast, an infinite number of combinations are logically possible for keylock switches by elongating the length of the key data. The longer the key data, the more difficult it becomes to forge the keylock switch with the result of the improvement of security.
Therefore, security of a higher level can be secured by replacing the combination of the metal key with the metal lock by a combination of a keylock switch with an electronic keylock or a combination of a metal lock with an electronic keylock.
In practice, however, there is a limit to the length of the personal identification number one can bear in mind, and this in turn limits security that is expected in the system using the input of the personal identification number or the password as the key.
On the other hand, the keylock switch using a storage media such as an IC card, a magnetic card or a bar code label can store key data having a sufficient length. Therefore, an electronic keylock system employing such a keylock switch is expected to provide security of high level.
To input the key data written to the storage media described above, however, both hardware and software of a large scale such as an IC card reader or a magnetic card reader are necessary.
The IC card used ordinarily, for example, has eight output terminals for outputting in parallel the data stored in a memory in an 8-bit unit. Therefore, a contact type IC card reader that is directly connected to the output terminals and receives the data has at least eight input terminals and a wiring circuit for transmitting in parallel the signals it receives to a checking part. A system that reads in a non-contact arrangement the key data stored in the memory of the IC card must include a radio transmission device for transmitting the key data on the IC card and means for receiving the key data on the IC card reader. A magnetic head and a demodulator are indispensable for the magnetic card reader. To read the bar code symbol, a bar code scanner and a demodulator are also indispensable.
As described above, the electronic keylock system using the storage media as the keylock switch requires many system constituents, and thus is more expensive than the combination of the metal key with the metal lock. Also, because of the need for many constituents, there is a limit to the reduction of the size of both keylock switch and electronic keylock.
For the reasons described above, the system using the keylock switch and the electronic keylock has been adopted for only those applications which require security of a high degree, such as research institutes and factories.
On the other hand, a growing number of trespassing on small-scale buildings such as ordinary houses and offices, theft of cars, illegal transaction through automated teller machines, illegal utilization of personal computers, and so forth, have become a serious problem in recent years.
It is an object of the present invention to provide reasonably-priced and compact keylock switch and keylock switch system that can guarantee safety from trespassing on small-scale buildings such as ordinary houses and offices, theft of cars, illegal transaction through automated teller machines, illegal utilization of personal computers, and so forth.
It is another object of the present invention to drastically expand the application field of a keylock switch and a keylock switch system by accomplishing an reasonably-priced and compact keylock switch and a keylock switch system using the keylock switch.
It is still another object of the present invention to accomplish a keylock switch that still has the function of a conventional lock formed of metal members and a keylock switch system using the keylock switch, and apply them in fields where metal keys are widely used, to improve security by improving the drawbacks of the metal key.
It is still another object of the present invention to quickly reset an internal state of a keylock switch after output of key data is completed, to prepare for the next use.
It is a further object of the present invention to provide an art to reliably deliver only a signal representing key data from a keylock switch to an electronic keylock, to stably detect the signal representing key data in the electronic keylock.
The objects described above can be accomplished by a first keylock switch having a configuration in which a charge storing section is charged by power supplied through first and second terminals, and a read section reads key data stored in a memory by utilizing power stored in the charge storing section and outputs the key data through the first and second terminals.
In the first keylock switch described above, the terminals provided to the keylock switch can be limited to only two. Therefore, it is possible to minimize both the space for the terminals themselves and the space for wiring the terminals to circuit elements.
The objects described above can be accomplished by a second keylock switch having a configuration in which a keylock switch circuit comprising a charge storing section, a memory and a read section is buried into an insulating part covering at least a part of a head portion of a metal key, a first terminal is disposed at a portion at which the insulating part and the metal key keep contact, and a second terminal is disposed on a surface of the insulating part at which the insulating part is out of contact with the metal key.
In the second keylock switch having the configuration described above, the metal key itself is used as the first terminal. Therefore, the number of a terminal to be disposed afresh is limited to one, and a function of inputting key data can be added to the original function of the metal key itself.
The objects described above can be accomplished by a first keylock switch system comprising a first keylock switch and a first electronic keylock, the first keylock switch having a configuration in which a charge storing section is charged by power supplied through first and second terminals, and a read section reads key data stored in a memory and outputs the key data through the first and second terminals, the first electronic keylock including third and fourth terminals for forming one junction when they come into contact with the first and second terminals, respectively, a power source for supplying power to the keylock switch through the third and fourth terminals, and a detecting section for detecting key data from a signal inputted through the third and fourth terminals.
In the first keylock switch system having the configuration described above, the contacts between the first keylock switch and the first electronic keylock can be limited to only two points. Therefore, in both first keylock switch and first electronic keylock, it is possible to minimize the space for the terminals themselves and the space required for wiring the terminals to circuit elements.
The objects described above can be accomplished by a second keylock switch system comprising a second keylock switch and a second electronic keylock, the second keylock switch having a configuration in which a keylock switch circuit comprising a charge storing section, a memory and a read section is buried into an insulating part covering at least a part of a head portion of a metal key, a first terminal is disposed at a portion at which the insulating part and the metal key keep mutual contact and a second terminal is disposed on a surface of the insulating part at which the insulating part is out of contact from the metal key, the second electronic keylock including an electronic keylock circuit comprising a third terminal so disposed as to keep contact with a metal part contacting the metal key, a fourth terminal for forming a junction when coming into contact with the second terminal, a power source for supplying power to the second keylock switch through the third and fourth terminals, and a detecting section for detecting key data from a signal inputted through the third and fourth terminals.
In the second keylock switch system described above, one of the two junctions is formed when the metal key is inserted into the metal part that constitutes the lock. Therefore, the number of the terminal to be disposed afresh on the second keylock switch and on the second electronic lock is limited to one. Furthermore, a function of inputting the key data and a function of actuating a locking or a releasing operation in accordance with the acceptance of the key data can be added to the function that the combination of the metal key with the metal lock originally has.
The objects described above can be respectively accomplished by third and fourth keylock switches each including, in addition to the first or second keylock switch, a rectifying section for restricting power supplying directions between the first terminal and the charge storing section and between the second terminal and the charge storing section.
The third and fourth keylock switches having the configuration described above can output the signal representing the key data stored in the memory without being affected by power stored in the charge storing section.
The objects described above can be accomplished by a third keylock switch system comprising a third keylock switch and a first electronic keylock and by a fourth keylock switch system comprising a fourth keylock switch and a second electronic keylock.
In the third and fourth keylock switch systems having the configurations described above, rectification of the rectifying section provided in the third or fourth keylock switch can output the signal representing key data stored in the memory without being affected the power stored in the charge storing section, and can transmit the key data to the detecting section.
The objects described above can be accomplished by, in addition to the first or second keylock switch of the first or second keylock switch system, a fifth or sixth keylock switch including a discharging section for discharging power remaining in the charge storing section provided in the keylock switch, in which the discharging is done in accordance with opening the two contacts formed between the keylock switch and the electronic keylock.
In the fifth and sixth keylock switches respectively having the configurations described above, the discharging section discharges power remaining in the charge storing section in accordance with the release of the junction between the keylock switch and the electronic keylock. Therefore, each component in the keylock switch can be quickly reset, so that the keylock switch can be ready for the next junction.
The objects described above can be accomplished by, in addition to the first electronic keylock provided to the first keylock switch system or the second electronic keylock provided to the second keylock switch system, third and fourth electronic keylocks each including an isolating section for isolating an AC signal appearing between the third and fourth terminals from the power source.
Since the third and fourth electronic keylocks described above include the isolating section, the read section can transmit to the detecting section the signal outputted through the two junctions without being affected by the power source.